TY290 Piston removal (the saga begins)
Bought a Farm Pro 2420 the other day that was getting oil in the water. The owner explained that he bought it from a guy who had purchased it new around 2000-2001, the original owner was supposedly bush hogging and it died in the middle of the field with water in the oil. The guy I bought it from thought it was the head or head gasket and bought it, said he had to load it in the middle of the field and help unhook the bush hog. If any of this is true I will never know but I feel like the guy was being honest.
He included a near complete set of gaskets, minus the head gasket and valve cover gasket and said that he had removed the head, had a local shop (major city) check the head for cracks and replace the valve guides.
I thought, eh, no problem, pop the liners and replace the o-rings since the speed it was loosing coolant was way too fast for any cracked block I'd ever seen.
Tear down went extremely easy as expected until I got to the pistons. I decided to start with the rear piston. First off the rod bolt seemed to be torqued to around 200 foot pounds but I did get them loose with a cheater bar about 3 feet long. The rod cap was very difficult to remove and I actually had to drive one of the rod bolts completely out before it would break free from it's home. Once it did slivers of bearing dropped on my head. Ahh, sigh, so much for some gaskets and o-rings to fix it. As I'm turning the crank to allow the piston to be pulled I notice what looks like a soldered or brazed oil hole. Sure enough there is no oil hole. Apparently with the rod bolt over tightened by king kong with an impact gun had allowed the oil hole to shave the bearing, ironically I believe the cheap Chinese bearings may have actually saved the crank. There are no gouges, only high spots of soft bearing material which may clean up.
Now the trouble begins, I work night shift so on my days off I'm up all night and working in the dark with over head lights, definitely not the all filling sun light of day time. I tried to pull the piston out the top with no results and notice one side of it where the wrist pin goes through that the piston appears to have hit some thing at some point. I worked for several hours before I finally thought to check the remaining rod bolt, sure enough it was hanging over the edge of the rod preventing it from coming out of the cylinder. Tap that bolt out and it slides right out. After the piston is removed it like the piston came too far out of the cylinder at the bottom of the stroke and twisted before being rammed back into it's bore. Crap, this keeps getting better. The cylinder o-rings can be seen laying on the ground, hung in the oil strainer and dangling from between the liner and the block.
I move on to the front piston, the rod bolts (nuts) seem normally torqued, the rod cap came off as it should once breaking the vacuum of the oil, the piston and rod slide out normally and easily. The front sleeve looks longer than the rear? Huh? The front one measures 6 3/4 inches, the rear one........ 5 5/8 inches? WTH!? Go back and look at the damage to the piston, it looks like the wrist pin was dropping below the bottom of the liner and the guy finally put enough load on it to cause the piston to cant just enough to wedge everything together, prob the reason the rear cylinder o-rings are dangling the way they are.
I'm just praying I can clean the crank up enough to use it, don't really want to have to put a complete rebuild into a tractor that I only plan to bush hog with while I mechanically restore my little Yanmar. Just moving this thing onto the trailer I really like the idea of the creeper box, never had one of those and REALLY liked it. Hope this thing isn't a lost cause but even with all it's problems it ran great loading it onto the trailer.
Husq YTH 2454 (2008)
Craftsman GT5000 (2005,6speed) sold
FarmPro 2420 (project)
Last edited by commrad; 03-24-2012 at 10:24 AM.